Nephritis Associated with Infectious Bronchitis Virus Cal99 Variant in Game Chickens

• Published in: Avian diseases 2011-09, Vol.55 (3), p.422-428
• Main Authors: França, M, Woolcock, P. R, Yu, M, Jackwood, M. W, Shivaprasad, H. L
• Format: Article
• Language: English
• Subjects: Animals; Antigens; Antigens, Viral - metabolism; Cal99 variant; California; Chickens; Coronavirus Infections - genetics; Coronavirus Infections - pathology; Coronavirus Infections - veterinary; Coronavirus Infections - virology; Epithelial cells; Epithelium; Infectious bronchitis virus; Infectious bronchitis virus - genetics; Infectious bronchitis virus - immunology; Infectious bronchitis virus - isolation & purification; Infectious bronchitis virus - pathogenicity; Kidney - pathology; Kidneys; Molecular Sequence Data; Mucosa; Nephritis; Nephritis - pathology; Nephritis - veterinary; Nephrosis - pathology; Nephrosis - veterinary; Organ Specificity; Phylogeny; Poultry Diseases - genetics; Poultry Diseases - pathology; Poultry Diseases - virology; Regular s; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Trachea; Ureter - physiopathology; Viruses
• ISSN: 0005-2086; 1938-4351
• DOI: 10.1637/9417-060510-Reg.1

Infectious bronchitis virus (IBV) Cal99 variant was isolated from the kidneys of seven 2–5-mo-old game chickens with nephritis and respiratory disease. IBV Cal99 variant is usually associated with respiratory disease in broiler chickens in California. Macroscopically, the majority of the birds had moderately to severely enlarged and mottled pale kidneys, with increased urates in the ureters. Microscopically, most of the birds had acute nephrosis and interstitial nephritis. The birds also had sinusitis, tracheitis, bronchopneumonia, airsacculitis, salivary gland adenitis, and lymphoid depletion in the thymus and bursa of Fabricius. Immunohistochemistry was strongly positive for IBV antigen in the cytoplasm of tubular epithelial cells in the kidneys and also in the epithelium of the respiratory tract, salivary glands, proventriculus, intestine, and bursa of Fabricius. Infectious bronchitis virus was isolated from the trachea, lungs, kidneys, and cecal tonsils. Sequencing of the hypervariable region of the S1 gene of the kidney IBV isolate, designated IBV/CA99variant/07, revealed that the virus was 98% homologous to the Cal99 serotype of IBV.